Message ID | 151801810352.29167.4832480228518630626.stgit@bahia.lan |
---|---|
State | New |
Headers | show |
Series | migration: improve documentation of postcopy-ram | expand |
On 02/07/2018 09:41 AM, Greg Kurz wrote: > This capability must have the same value on both source and destination, > otherwise migration fails (commit 875fcd013ab6 "migration: incoming > postcopy advise sanity checks"). > > Let's write it down in various places where postcopy-ram is documented. > > Signed-off-by: Greg Kurz <groug@kaod.org> > --- > docs/devel/migration.rst | 4 ++-- > hmp-commands.hx | 3 ++- > qapi/migration.json | 10 ++++++---- > 3 files changed, 10 insertions(+), 7 deletions(-) Reviewed-by: Eric Blake <eblake@redhat.com>
* Greg Kurz (groug@kaod.org) wrote: > This capability must have the same value on both source and destination, > otherwise migration fails (commit 875fcd013ab6 "migration: incoming > postcopy advise sanity checks"). > > Let's write it down in various places where postcopy-ram is documented. > > Signed-off-by: Greg Kurz <groug@kaod.org> Thanks, Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > --- > docs/devel/migration.rst | 4 ++-- > hmp-commands.hx | 3 ++- > qapi/migration.json | 10 ++++++---- > 3 files changed, 10 insertions(+), 7 deletions(-) > > diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst > index bf97080dac2f..9d1b7657f0cf 100644 > --- a/docs/devel/migration.rst > +++ b/docs/devel/migration.rst > @@ -387,8 +387,8 @@ doesn't finish in a given time the switch is made to postcopy. > Enabling postcopy > ----------------- > > -To enable postcopy, issue this command on the monitor prior to the > -start of migration: > +To enable postcopy, issue this command on the monitor (both source and > +destination) prior to the start of migration: > > ``migrate_set_capability postcopy-ram on`` > > diff --git a/hmp-commands.hx b/hmp-commands.hx > index 15620c94d3fc..d26eb4119b9d 100644 > --- a/hmp-commands.hx > +++ b/hmp-commands.hx > @@ -1041,7 +1041,8 @@ ETEXI > .params = "", > .help = "Followup to a migration command to switch the migration" > " to postcopy mode. The postcopy-ram capability must " > - "be set before the original migration command.", > + "be set on both source and destination before the " > + "original migration command .", > .cmd = hmp_migrate_start_postcopy, > }, > > diff --git a/qapi/migration.json b/qapi/migration.json > index 4cd3d1315884..7f465a1902ce 100644 > --- a/qapi/migration.json > +++ b/qapi/migration.json > @@ -327,8 +327,10 @@ > # to speed up convergence of RAM migration. (since 1.6) > # > # @postcopy-ram: Start executing on the migration target before all of RAM has > -# been migrated, pulling the remaining pages along as needed. NOTE: If > -# the migration fails during postcopy the VM will fail. (since 2.6) > +# been migrated, pulling the remaining pages along as needed. The > +# capacity must have the same setting on both source and target > +# or migration will not even start. NOTE: If the migration fails during > +# postcopy the VM will fail. (since 2.6) > # > # @x-colo: If enabled, migration will never end, and the state of the VM on the > # primary side will be migrated continuously to the VM on secondary > @@ -742,8 +744,8 @@ > # @migrate-start-postcopy: > # > # Followup to a migration command to switch the migration to postcopy mode. > -# The postcopy-ram capability must be set before the original migration > -# command. > +# The postcopy-ram capability must be set on both source and destination > +# before the original migration command. > # > # Since: 2.5 > # > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On Wed, 7 Feb 2018 15:55:01 +0000 "Dr. David Alan Gilbert" <dgilbert@redhat.com> wrote: > * Greg Kurz (groug@kaod.org) wrote: > > This capability must have the same value on both source and destination, > > otherwise migration fails (commit 875fcd013ab6 "migration: incoming > > postcopy advise sanity checks"). > > > > Let's write it down in various places where postcopy-ram is documented. > > > > Signed-off-by: Greg Kurz <groug@kaod.org> > > Thanks, > > Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > Who should pick this up ? > > --- > > docs/devel/migration.rst | 4 ++-- > > hmp-commands.hx | 3 ++- > > qapi/migration.json | 10 ++++++---- > > 3 files changed, 10 insertions(+), 7 deletions(-) > > > > diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst > > index bf97080dac2f..9d1b7657f0cf 100644 > > --- a/docs/devel/migration.rst > > +++ b/docs/devel/migration.rst > > @@ -387,8 +387,8 @@ doesn't finish in a given time the switch is made to postcopy. > > Enabling postcopy > > ----------------- > > > > -To enable postcopy, issue this command on the monitor prior to the > > -start of migration: > > +To enable postcopy, issue this command on the monitor (both source and > > +destination) prior to the start of migration: > > > > ``migrate_set_capability postcopy-ram on`` > > > > diff --git a/hmp-commands.hx b/hmp-commands.hx > > index 15620c94d3fc..d26eb4119b9d 100644 > > --- a/hmp-commands.hx > > +++ b/hmp-commands.hx > > @@ -1041,7 +1041,8 @@ ETEXI > > .params = "", > > .help = "Followup to a migration command to switch the migration" > > " to postcopy mode. The postcopy-ram capability must " > > - "be set before the original migration command.", > > + "be set on both source and destination before the " > > + "original migration command .", > > .cmd = hmp_migrate_start_postcopy, > > }, > > > > diff --git a/qapi/migration.json b/qapi/migration.json > > index 4cd3d1315884..7f465a1902ce 100644 > > --- a/qapi/migration.json > > +++ b/qapi/migration.json > > @@ -327,8 +327,10 @@ > > # to speed up convergence of RAM migration. (since 1.6) > > # > > # @postcopy-ram: Start executing on the migration target before all of RAM has > > -# been migrated, pulling the remaining pages along as needed. NOTE: If > > -# the migration fails during postcopy the VM will fail. (since 2.6) > > +# been migrated, pulling the remaining pages along as needed. The > > +# capacity must have the same setting on both source and target > > +# or migration will not even start. NOTE: If the migration fails during > > +# postcopy the VM will fail. (since 2.6) > > # > > # @x-colo: If enabled, migration will never end, and the state of the VM on the > > # primary side will be migrated continuously to the VM on secondary > > @@ -742,8 +744,8 @@ > > # @migrate-start-postcopy: > > # > > # Followup to a migration command to switch the migration to postcopy mode. > > -# The postcopy-ram capability must be set before the original migration > > -# command. > > +# The postcopy-ram capability must be set on both source and destination > > +# before the original migration command. > > # > > # Since: 2.5 > > # > > > -- > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK >
* Greg Kurz (groug@kaod.org) wrote: > On Wed, 7 Feb 2018 15:55:01 +0000 > "Dr. David Alan Gilbert" <dgilbert@redhat.com> wrote: > > > * Greg Kurz (groug@kaod.org) wrote: > > > This capability must have the same value on both source and destination, > > > otherwise migration fails (commit 875fcd013ab6 "migration: incoming > > > postcopy advise sanity checks"). > > > > > > Let's write it down in various places where postcopy-ram is documented. > > > > > > Signed-off-by: Greg Kurz <groug@kaod.org> > > > > Thanks, > > > > Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > > > > Who should pick this up ? I was going to pick it up in a migration pull today. Dave > > > --- > > > docs/devel/migration.rst | 4 ++-- > > > hmp-commands.hx | 3 ++- > > > qapi/migration.json | 10 ++++++---- > > > 3 files changed, 10 insertions(+), 7 deletions(-) > > > > > > diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst > > > index bf97080dac2f..9d1b7657f0cf 100644 > > > --- a/docs/devel/migration.rst > > > +++ b/docs/devel/migration.rst > > > @@ -387,8 +387,8 @@ doesn't finish in a given time the switch is made to postcopy. > > > Enabling postcopy > > > ----------------- > > > > > > -To enable postcopy, issue this command on the monitor prior to the > > > -start of migration: > > > +To enable postcopy, issue this command on the monitor (both source and > > > +destination) prior to the start of migration: > > > > > > ``migrate_set_capability postcopy-ram on`` > > > > > > diff --git a/hmp-commands.hx b/hmp-commands.hx > > > index 15620c94d3fc..d26eb4119b9d 100644 > > > --- a/hmp-commands.hx > > > +++ b/hmp-commands.hx > > > @@ -1041,7 +1041,8 @@ ETEXI > > > .params = "", > > > .help = "Followup to a migration command to switch the migration" > > > " to postcopy mode. The postcopy-ram capability must " > > > - "be set before the original migration command.", > > > + "be set on both source and destination before the " > > > + "original migration command .", > > > .cmd = hmp_migrate_start_postcopy, > > > }, > > > > > > diff --git a/qapi/migration.json b/qapi/migration.json > > > index 4cd3d1315884..7f465a1902ce 100644 > > > --- a/qapi/migration.json > > > +++ b/qapi/migration.json > > > @@ -327,8 +327,10 @@ > > > # to speed up convergence of RAM migration. (since 1.6) > > > # > > > # @postcopy-ram: Start executing on the migration target before all of RAM has > > > -# been migrated, pulling the remaining pages along as needed. NOTE: If > > > -# the migration fails during postcopy the VM will fail. (since 2.6) > > > +# been migrated, pulling the remaining pages along as needed. The > > > +# capacity must have the same setting on both source and target > > > +# or migration will not even start. NOTE: If the migration fails during > > > +# postcopy the VM will fail. (since 2.6) > > > # > > > # @x-colo: If enabled, migration will never end, and the state of the VM on the > > > # primary side will be migrated continuously to the VM on secondary > > > @@ -742,8 +744,8 @@ > > > # @migrate-start-postcopy: > > > # > > > # Followup to a migration command to switch the migration to postcopy mode. > > > -# The postcopy-ram capability must be set before the original migration > > > -# command. > > > +# The postcopy-ram capability must be set on both source and destination > > > +# before the original migration command. > > > # > > > # Since: 2.5 > > > # > > > > > -- > > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK > > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
On Wed, 14 Feb 2018 09:45:50 +0000 "Dr. David Alan Gilbert" <dgilbert@redhat.com> wrote: > * Greg Kurz (groug@kaod.org) wrote: > > On Wed, 7 Feb 2018 15:55:01 +0000 > > "Dr. David Alan Gilbert" <dgilbert@redhat.com> wrote: > > > > > * Greg Kurz (groug@kaod.org) wrote: > > > > This capability must have the same value on both source and destination, > > > > otherwise migration fails (commit 875fcd013ab6 "migration: incoming > > > > postcopy advise sanity checks"). > > > > > > > > Let's write it down in various places where postcopy-ram is documented. > > > > > > > > Signed-off-by: Greg Kurz <groug@kaod.org> > > > > > > Thanks, > > > > > > Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > > > > > > > Who should pick this up ? > > I was going to pick it up in a migration pull today. > Cool, thanks ! > Dave > > > > > --- > > > > docs/devel/migration.rst | 4 ++-- > > > > hmp-commands.hx | 3 ++- > > > > qapi/migration.json | 10 ++++++---- > > > > 3 files changed, 10 insertions(+), 7 deletions(-) > > > > > > > > diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst > > > > index bf97080dac2f..9d1b7657f0cf 100644 > > > > --- a/docs/devel/migration.rst > > > > +++ b/docs/devel/migration.rst > > > > @@ -387,8 +387,8 @@ doesn't finish in a given time the switch is made to postcopy. > > > > Enabling postcopy > > > > ----------------- > > > > > > > > -To enable postcopy, issue this command on the monitor prior to the > > > > -start of migration: > > > > +To enable postcopy, issue this command on the monitor (both source and > > > > +destination) prior to the start of migration: > > > > > > > > ``migrate_set_capability postcopy-ram on`` > > > > > > > > diff --git a/hmp-commands.hx b/hmp-commands.hx > > > > index 15620c94d3fc..d26eb4119b9d 100644 > > > > --- a/hmp-commands.hx > > > > +++ b/hmp-commands.hx > > > > @@ -1041,7 +1041,8 @@ ETEXI > > > > .params = "", > > > > .help = "Followup to a migration command to switch the migration" > > > > " to postcopy mode. The postcopy-ram capability must " > > > > - "be set before the original migration command.", > > > > + "be set on both source and destination before the " > > > > + "original migration command .", > > > > .cmd = hmp_migrate_start_postcopy, > > > > }, > > > > > > > > diff --git a/qapi/migration.json b/qapi/migration.json > > > > index 4cd3d1315884..7f465a1902ce 100644 > > > > --- a/qapi/migration.json > > > > +++ b/qapi/migration.json > > > > @@ -327,8 +327,10 @@ > > > > # to speed up convergence of RAM migration. (since 1.6) > > > > # > > > > # @postcopy-ram: Start executing on the migration target before all of RAM has > > > > -# been migrated, pulling the remaining pages along as needed. NOTE: If > > > > -# the migration fails during postcopy the VM will fail. (since 2.6) > > > > +# been migrated, pulling the remaining pages along as needed. The > > > > +# capacity must have the same setting on both source and target > > > > +# or migration will not even start. NOTE: If the migration fails during > > > > +# postcopy the VM will fail. (since 2.6) > > > > # > > > > # @x-colo: If enabled, migration will never end, and the state of the VM on the > > > > # primary side will be migrated continuously to the VM on secondary > > > > @@ -742,8 +744,8 @@ > > > > # @migrate-start-postcopy: > > > > # > > > > # Followup to a migration command to switch the migration to postcopy mode. > > > > -# The postcopy-ram capability must be set before the original migration > > > > -# command. > > > > +# The postcopy-ram capability must be set on both source and destination > > > > +# before the original migration command. > > > > # > > > > # Since: 2.5 > > > > # > > > > > > > -- > > > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK > > > > > > -- > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst index bf97080dac2f..9d1b7657f0cf 100644 --- a/docs/devel/migration.rst +++ b/docs/devel/migration.rst @@ -387,8 +387,8 @@ doesn't finish in a given time the switch is made to postcopy. Enabling postcopy ----------------- -To enable postcopy, issue this command on the monitor prior to the -start of migration: +To enable postcopy, issue this command on the monitor (both source and +destination) prior to the start of migration: ``migrate_set_capability postcopy-ram on`` diff --git a/hmp-commands.hx b/hmp-commands.hx index 15620c94d3fc..d26eb4119b9d 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1041,7 +1041,8 @@ ETEXI .params = "", .help = "Followup to a migration command to switch the migration" " to postcopy mode. The postcopy-ram capability must " - "be set before the original migration command.", + "be set on both source and destination before the " + "original migration command .", .cmd = hmp_migrate_start_postcopy, }, diff --git a/qapi/migration.json b/qapi/migration.json index 4cd3d1315884..7f465a1902ce 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -327,8 +327,10 @@ # to speed up convergence of RAM migration. (since 1.6) # # @postcopy-ram: Start executing on the migration target before all of RAM has -# been migrated, pulling the remaining pages along as needed. NOTE: If -# the migration fails during postcopy the VM will fail. (since 2.6) +# been migrated, pulling the remaining pages along as needed. The +# capacity must have the same setting on both source and target +# or migration will not even start. NOTE: If the migration fails during +# postcopy the VM will fail. (since 2.6) # # @x-colo: If enabled, migration will never end, and the state of the VM on the # primary side will be migrated continuously to the VM on secondary @@ -742,8 +744,8 @@ # @migrate-start-postcopy: # # Followup to a migration command to switch the migration to postcopy mode. -# The postcopy-ram capability must be set before the original migration -# command. +# The postcopy-ram capability must be set on both source and destination +# before the original migration command. # # Since: 2.5 #
This capability must have the same value on both source and destination, otherwise migration fails (commit 875fcd013ab6 "migration: incoming postcopy advise sanity checks"). Let's write it down in various places where postcopy-ram is documented. Signed-off-by: Greg Kurz <groug@kaod.org> --- docs/devel/migration.rst | 4 ++-- hmp-commands.hx | 3 ++- qapi/migration.json | 10 ++++++---- 3 files changed, 10 insertions(+), 7 deletions(-)